Striking model-turned-actress, she was the granddaughter of novelist Ernest Hemingway. She grew up on Hemingway's farms in Cuba and Ketchum, Idaho, where he had committed suicide. Having decided on a modeling career, she quickly rose to the top, commanding enormous fees and launching Faberge perfume, which she had also helped to develop. She leveraged her popularity to move into a lackluster film career, appearing most notably in Lipstick (1976) about a rape victim and her younger sister, played by Margaux's sister Mariel. The film was lambasted by critics because of its lurid content and her performance, but did spark a California law that prohibited mention of a victim's sexual history during a rape trial. The rest of her film career was largely forgettable, and her two marriages failed amidst her problems with addiction and substance abuse.